<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<input type="text" id="input1" /><br />
		<input type="text" id="input2" /><br />
		<script>
			input1.onkeydown=function(e){
				console.log("按下");
				console.log(e.key);
				console.log(e.keyCode);
			}
			input1.onkeyup=function(e){
				console.log("抬起");
				console.log(e.key);
				console.log(e.keyCode);
			}
			input1.onkeypress=function(e){
				console.log("按了");
				console.log(e.key);
				console.log(e.keyCode);
			}
			input2.onkeydown=function(e){
				if(e.keyCode>=48&&e.keyCode<=57){
					
				}else{
					console.log("不是数字");
					event.preventDefault();
				}
			}
		</script>
	</body>
</html>
